Here's some fuel for the argument that even in light of the Supreme Court's decision in Citizens United, major corporations will think twice before jumping at the chance to fund independent expenditure efforts this fall.

Gregg Steinhafel, the CEO of the retail giant Target, formally apologized in a letter to the company's employees Thursday for writing a $150,000 check to the conservative group MN Forward, a 527 that's running ads in support of Minnesota gubernatorial candidate Tom Emmer (R).

Gay-rights groups flagged the donation from Steinhafel noting Emmer's opposition in the Minnesota state House to gay-rights legislation.

From The Associated Press:

Steinhafel said the contribution from the corporate treasury to a political effort, which until this year wasn't allowed, was designed to support his stance on economic issues. Ads run by the group were focused on budget policy, not social issues.

"While I firmly believe that a business climate conducive to growth is critical to our future, I realize our decision affected many of you in a way I did not anticipate, and for that I am genuinely sorry," Steinhafel wrote.

He added, "The diversity of our team is an important aspect of our unique culture and our success as a company, and we did not mean to disappoint you, our team or our valued guests."

OutFront Minnesota, a gay-rights advocacy group, posted an open letter urging Target to take back its money from MN Forward. And "Boycott Target" Facebook groups began to appear.

In the wake of the court's decision in the Citizens United case, critics warned corporate spending could overwhelm the 2010 midterm elections. But others predicted corporations were likely to proceed with more caution given that they have brands to protect.

The AP notes that Red Wing Shoes and Best Buy are among a handful of other companies that have written checks to MN Forward.